Airship



March 21, 1933. w. v. N. POWELSON ET AL 1,902,519

AIRSHIP Original Filed Sept. 1921 Patented Mar. 21, 1933 v UNITED STATES PATENT OFFICE wiLrmn v. N. rowELsoN, or new YORK, N. Y., AND'WARREN rnavnm, .or'slm" BEBNABDINO, CALIFORNIA f nmsrirr Original application filed Se tember's, 1921, Serial No. 498,605. Divided and this application filed March 17,1931. Seria1"No.523,250.

valuable gas when gas has hadto be-discharged because of ascent from one elevation to another, as, for example, from ground levels to cruising levels. One ofthe objects of the present invention is to provide an improved means to avoid such waste,

This is conveniently accomplished, according to the present invention, 'bypro? viding in each said chamber or compartment of the shipsframe a plurality of gas containers which are external to each other and which together fill the chamber,ian

arrangement and construction which herein for brevity will be designated by the single 1 word complementary. These complementary containers are charged with different kinds of gas, one being charged with the expensive and high grade principal lifting gas, as hydrogen or helium, herein called the main body of'lifting gas, and the other being charged with a gas herein called the auxiliary gas, whose value is low, because of its inferior quality, such as spent lifting gas or air. Both of said containers are equipped with means for escape of contents to the atmosphere. Then when the main body of lifting gas tends to expand, dueto decreasing density of atmosphere on ascending from ground to cruising levels, the expansion of the containers charged with the valuable lifting gas is-permitted, without wastage of contents, because of the complementary containers of auxiliary gas being arranged to yield commensurately. The result is that the latter are vented to the atmosphere before wastage of pure lifting gas begins. I

It is a particular feature that the complement-ary containers are external toveach other. It follows that the'body of poor gas in the auxiliary container is in proximity to the high quality'gas only along one side, or perhaps two sides, of, its total surface.

And on that side orsidesthe two gases are I separated by the two layers of fabric which respectively constitute the container walls, j

as well as a film of atmospheric air which is between the walls. 1

It has been found that there is a tendency of air to pass from air into hydrogen or helium, diffusing through the pores of the fabric wall that holds the-lifting gas,;and

this infiltration is a pronounced evil in that it gradually vitiates the expensive gas for lifting purposes. We have discovered a remedy by placing the lifting gas under pressure. such that the contained gas tends to pass outward through the pores of the fabiliary container, as by pumping more gas' into it, so that the contents of these twomay be of equal pressure, and both of them greater than the local atmospheric pressure,

without the equilibrium ofpressure of gas in the auxiliary chamber with pressureof poor gas orair into gradegas. i i

In the accompanying drawing, forming a part hereof, Figure 1 represents more or less diagrammatically an airship provided with complementary gas containers, as hereing gas which is of high quality in the sense that, whatever he itskind or quality in an absolute sense, its quality 15 high as the term is used here because it is relatively uncontaminated by infiltration of air. But

containers 22eare filled with the more or less spent lifting gas, or with air, or other less expensive and lessgood gas, as for example any -cheaner buoyant gas, which is to be vented to the atmosphere when decrease of atmosphericlocal pressure requires expansion of the main body of lifting gas.

I Preferably these containers '21 and 22 are in the form of collapsible gas bags contained within the confining walls of the chamber or other limited space, the bags 21 being exterior-to the bags 22. By-arrangingthem in this manner and using a fabric at least a portion of whichis collapsible, as indicacd in the drawing, container 22 is always complementary to container 21, whatever be their relative stages of expansion or contraction.

7 As shown in Figure 3, a header 7 with branch pipes 125 having control valves 127 may serve to connect the several main-gas bags 21 where more than one such bag is employed for each chamber'section of the dirigible. branch pipes 126 having control valves 128 may connect the several auxiliary containers 22 forair or inferior gas. To this end, andwith the aid of apparatus and valves whichjitis not necessary to illustrate but whose presence is implied from and typified by the respective representations of headers 7 and 120 (which lead from and to suitable apparatus and valves that are not shown), air or gas may be removed from or blown into any one of the bags as desired, or the contents of each system may be permitted 'interflow, among the bags of its own system.

It will be understood that automatic valves may be providedand pumping apparatus automatic or otherwise, either connected with these headers or directly con-' nected with the bags, by which the pressure in both containers can be maintained above that of external air int-he locality Wherever the, ship may happen to be; and moreover these valves may also be so related that, in case of a predetermined too great excess of gas pressure over atmosphere, the auxiliary gas discharge valveshall be set to discharge at a lower pressure than does the discharge valve for the main body of lifting gas. This may happen on rise in elevation; on descent the automatic pumpare not illustrated herein.

bags 21 expand Similarly header 120 with gas into the auxiliary container from atmose phere or, from other source of supply, 111 order to keep the two complementary bags swelledrout against atmosphere and at the desired pressure above atmosphere. As these devices are not part of the invention here claimed, and can otherwisebe known, they At'the beginning of a flight, the auxiliary bags 22 are filled with an inferior and less expensive gas than that which fills the main gas bags 21.; As theairship ascendsto its cruising altitude, the atmosphericpressure gradually decreases with the result that the gas in the bagstends to expand and would place its containing vwall in excessive tension if not allowed to expand. Gas in the auxiliary bags 22- is then allowed to escape to the atmosphere through appropriate relief valves, which preferably are automatic as above indicated, thus letting the, main by squeezing the auxiliary bags. V

This does not interfere with'the making of the lifting gas anactive element of the inventiomfor certain qualities which may be varied. from. time totime in the operation of the ship. In a typical instance, the gas containers of, a ship located at a station and about to-begin a-fiight are. furnished with gas at a predetermined temperature different from the local atmospheric-temperature. Under certain circumstances, this willbe at ahigher temperature and under others, at a temperature below the local ifs atmospheric vtemperature, as required, A quantity of such gas is provided and permitted to fill'the containers. I

The balance 22 of the space-within the airship, to be occupied by-Zlifting gas when the mam gas containers 21 have expanded j fully, is at the moment of ascent occupied by air or bya lifting gas of less valuable quality from the gas used in fiight, Such air or less valuable gas is confined in the flexible containers 22, so situated that when the uncontaminated lifting gasv attains a pressure to a predetermined degree above thatof the surrounding atmo'sphera'it will cause the inferior gas to escape. I I

The result is that when the pressure of the atmosphere decreases, as occurs in rising from the ground to a cruising altitude, the expansion ofthe cruising gas will not result in the discharge of such gas into the "atmos here until all 'the less" valuable as.

has first been discharged. By using a preheated'less-valnable gas for the auxiliary containers during the initial lift, in container thus fitted the installation s'oacean'd ioo Obviously, improvements and modificaalso, that the structure disclosed in the drawing is adapted for other usesthan that described, as, for example, for providing a container for fuel gas within the gas chambers of the ship.

The subject matter of this application 7 has been divided out of our co-pending application 498,605, filed September 6, 1921, for Airships. It is intended that the patent to be based on the present application shall cover, by suitable expression in the appended claims, whatever features of patentable novelty are found in the invention herein disclosed.

We claim: 1. In an a1rsh1p,an upper gas container for lifting gas and a lower gas container for gas of difierent properties, the two containers being external to each other, with atmospheric air intervening between them, but having contiguous walls, movable in unison and in harmony with expansion and I contraction of gas in the upper container, and means whereby gas flows out from the lower container in harmony with said expansion; the said contiguous wallsextend ing-in direction approximately normal to the direction of gravity, whereby mutual abrasion is minimized. p

2. In an airship deriving upward lift from lighter-than-air gas, and having two complementary gas containers, each of which is expansible and contractable, these two containers having freely movable contiguous walls; a quantity of lighter-than-air gas in one of said containers, comprising a main body of lifting gas; a quantity of lighter than-air gas in the other said container,.comprising an auxiliary body of lifting gas; an automatic release-to-atmosphere valve for each said container, adapted to hold gas within its container at a pressure above current external air pressure, and to discharge gas from within when the differential of the internal over the external pressure attains a predetermined value ;the co-operating combination of the two said containers, their freely movable said walls and their several said release valves, in which the said release valve of the auxiliary body is organized to open at a lower differential above the current atmospheric pressure than is the said release valve for the main body; whereby a rise of pressure diflerential of the main body above atmosphere acts through the movable walls 7 to expand while being retained in its said to raise pressure in the auxiliary body and thereby, by releasing gas from the auxiliary body, and by movement of contiguous walls,

main container.

3. In combination, in an airship deriving an upward lift from lighter-than-air cruising gas on board, a first flexible container, partially expanded, filled withsaid cruising gas; asecond flexible container; means to confine the said twocontainers.exteriorly of each other within a space havinga less cubic capacity than the sum of the cubic contents of the two said containers measured separately when fully inflated; there being gas releasing means for theauxiliary tainer, operated by increase of di erential of pressure of the cruising gas above current local atmospheric pressure; and, in the said second flexible container, a quantity of lighter-than-air auxiliarylifting gas of a diflerent quality from the cruising gas, being gas previously used for cruising purposes, but which, by reason of admixture of other gases with it, has become unsuited for cruising purposes. 7 a v Signed at San Bernardino, California, this eleventh day of November, 1930.

W'I'LFRID v, N. POWELSON, WARREN TRAVELL. r 

